Addison's disease

Question 1

What is Addison’s disease?

Answer 1

AI destruction of entire adrenal cortex = deficiency in aldosterone, cortisol and and androgens

Question 2

How does it present?

Answer 2

Lethargy 
Weakness
Anorexia 
Abdo pain, N/V
Wt loss
'Salt-craving'
Vitiligo 
Loss of body hair 
Hyperpigmentation - tanned skin (esp palmar creases)
HypoNa 
HyperK

Question 3

Addison’s is an example of what?

Answer 3

Adrenal insufficiency

Question 4

Which clinical feature allows you to differentiate between Addison’s and secondary causes of adrenal insufficiency?

Answer 4

Addison’s associated with hyperpigmentation whereas secondary adrenal insufficiency is not

Question 5

What is the pathophysiology of hyperpigmentation in Addison’s?

Answer 5

ACTH increases = stimulates melanocytes

Question 6

Name other causes of adrenal insuffiency

Answer 6

Secondary:
- Pituitary disorders - see LOW ACTH

Other:
- Exogenous glucocorticoid therapy

Question 7

What Ix do you do?

Answer 7

Short Synacthen test (IM)

• acts like ACTH
• measure serum cortisol levels before and after injection of synacthen
• a rise in cortisol to a certain level indicates adequate renal response

OTHERS:

Bloods

• adrenal AAB e.g. anti-21-hydroxylase
• HyperK
• HypoNa
• Hypoglycaemia

ABG
- metabolic acidosis

Question 8

How do you mx ?Addison’s pt acutely e.g. if hypotensive?

Answer 8

Measure serum cortisol

100mg hydrocortisone and saline immediately!!! No need to confirm dx first

Further 0.9% saline and 6hrly infusion of 100mg hydrocortisone until pt stable

Consider giving glucose if pt is hypoglycaemic

Once pt stable, give oral hydrocortisone every 8h

Question 9

What is the long-term mx?

Answer 9

Glucocorticoid and mineralocorticoid replacement therapy

Hydrocortisone - 2/3 doses (20-30mg per day)
Fludrocortisone

Educate pt:

• DO NOT miss GC dose
• MedicAlert bracelets/ steroid cards
• Adjust dose on sick days!!!!!!

Question 10

How is hydrocortisone dose adjusted on a sick day?

Answer 10

DOUBLE!!!!!!